Telematics units within mobile vehicles provide subscribers with connectivity to a telematics service provider (TSP). The TSP provides the subscriber with an array of services ranging from emergency call handling and stolen vehicle recovery to diagnostics monitoring and turn-by-turn navigation. Telematics units are often provisioned and activated at a point of sale when a subscriber purchases a telematics-equipped vehicle. Upon activation, the telematics unit can be utilized to provide a subscriber with the telematics services.
One of the services conventionally provided by TSPs is GPS navigation, which may include the provision of Turn-by-Turn (TBT) directions. To use GPS navigation, a user of the telematics unit may enter a destination, and the GPS component of the telematics unit may provide directions (e.g. through a display and/or through vocal instructions) to the user based on a calculated course from the user's current location to the user's destination. When a user does not follow the directions and goes off-course (i.e., when the position of the vehicle is not on the calculated course), the GPS unit may recalculate a new course for the user to take based on the vehicle's position when it goes off-course.
While this is often a helpful feature for users who accidentally take a wrong turn, miss a turn, or encounter some unanticipated obstacle (e.g. road closures), off-route notifications and course recalculation is often a source of annoyance for users when they occur while the user is actually on-route. For example, if the calculated route takes the user through a tunnel or a stacked bridge (or other type of areas where GPS navigation is prone to error), GPS positioning information may be lost or erroneous while the user is in the tunnel or stacked bridge, causing the GPS unit to present off-route notifications and route recalculation when not necessary. Such areas, including but not limited to stacked bridges, tunnels, etc., will hereinafter be referred to as “problem areas” for convenience.
Thus, it is an object in part to provide a system and method for processing GPS navigation such that traveling through areas such as tunnels and stacked bridges do not trigger off-route notifications. However, while this is an object underlying certain implementations of the invention, it will be appreciated that the invention is not limited to systems that solve the problems noted herein. Moreover, the inventors have created the above body of information merely for the convenience of the reader; the foregoing is a discussion of problems discovered and/or appreciated by the inventors, and is not an attempt to review or catalog the prior art.